Traditional combustion engines include an intake stroke followed by a compression stroke. Generally, a mixture of air and fuel is introduced into a combustion chamber of the engine during the intake stroke and thereafter compressed by a piston during the compression stroke. Compression of the air/fuel mixture significantly increases the temperature and pressure of the mixture. Autoignition may occur when the compressed air/fuel mixture reaches a temperature that causes it to spontaneously ignite prior to a spark plug firing to ignite the air/fuel mixture and may cause damage to the engine. Accordingly, design features of traditional combustion engines such as static compression ratio, forced induction capacity, power density, fuel economy, and fueling options are constrained by the limits of autoignition.